China’s Jing-Jin-Ji area has suffered severe haze pollution these years. To aim at this national issue, Anhui Institute of Optics and Fine Mechanics (AIOFM), Hefei Institutes of Physical Science established Lidar network to provide spatial distribution of aerosols in this haze pollution episode.

Since its establishment in China’s Jing-Jin-Ji area in 2013, lidar network has made remarkable contributions to air quality ensuring and effects reduction evaluation. Through the image of the distribution of haze thickness presented in the CCTV’s weather forecast, the lidar network offers the real-time and direct viewing of haze thickness distribution.

For now, there are still four lidar monitoring stations that serve Beijing and Tianjin areas, say, the Mentougou lidar station operates to monitor the pollutant transportation pathway along the piedmont of Taihang Mountains, the Gaocun lidar station in Tianjin to monitor the southeast pathway, the Jiande bridge lidar station to monitor the time-space distribution fine particles in the center of Beijing.

And in additon to the three lidar stations mentioned above, Yanqi lake lidar station was simultaneously set up in northernmost area of Beijing city to monitor the background concentration. This northernmost lidar network recorded the occurrence, development and dissipation of this heaviest haze episode in Beijing's winter since 2013.

For example, last winter, particles firstly appeared at the west lidar station in Mentougou at 21:49 Dec 15, which was located at the piedmont pathway of Taihang Mountains. Then the pollution layer sank rapidly at the lidar station in Gaocun at the southeast pathway at 22:33. Subsequently at 23:28, the particle extinction coefficient at the Beijing JIande bridge station rose to 1.5 km-1 . Finally at 19:40 on the next day, the heavy haze cast its impact on the northernmost Lidar station in Yanqi Lake. (as shown in figure1.)

Joining hands with China Meteorological Administration (CMA) Meteorological Observation Center, AIOFM will continue to apply lidar network to air pollution monitoring in mega-cities and the monitoring result in terms of images will act as an important indicator for air quality in the CCTV weather forecast.

 Figure1. Four lidar observing stations (Image by LV Lihui) 

Haze thickness observed by Jiande Bridge lidar stations from 16 December to 20 December (Image by LV Lihui)

Lidar network established by AIOFM (Image by LV Lihui)

Set up of lidar for fine particles monitoring (Image by LV Lihui)